Agglomeration process improves instant properties of powders and increases consumer appreciation, reduces losses during production, and facilitates the processability of these powders in the industry. Mushroom powders (MP) have been subjected to agglomeration process at different process parameters: inlet air temperature (50–80°C), atomizing pressure (0.5–1.5 bars), and sprayed pure water amount (20–50 g) and the effects of process parameters on the physical and morphological properties of MP were investigated. The inlet air temperature and pure water amount have a linear effect on moisture content, apparent density, particle size, and porosity. Emulsion stability index was affected by inlet air temperature and atomization pressure. The optimal process condition (70°C inlet temperature 0.5 bar atomizing pressure and 50 g pure water amount) was determined for minimization of moisture content, wetting time, as well as maximation of particle size, porosity, emulsifying and foaming properties, and solubility. The results suggested that improving instant and physical properties make easier the processability of these powders in the industry and increased emulsifying properties show a good opportunity for usage of agglomerated MP in the emulsion systems. Practical Applications: This study showed the effects of the agglomeration process on the physicochemical, morphological, instant, and emulsifying properties of mushroom powders. The improvement of these properties makes it possible to increase the application areas of mushroom powders as a food additive in different food formulas and emulsified products.